As a software developer and a horse owner, I would love to make this free web calculator better. All donations go to the web maintenance and development. Occasionally, I am going to buy my horses a bucket of carrots, because they are the reason why I started this web.

Facts About Horse Feeding

Feral versus Domestic Horses Feed Behaviour

Feral horses spend the majority of their time eating, which usually involves much walking between patches of food. While most of their food consists of grasses, the forage species consumed by feral horses varies daily and seasonally. The horse is well adapted to this type of food consumption. It has a small stomach built to handle continuous, small amounts of food, not large meals. Ingested food spends little time in the horse's stomach and small intestine and is rapidly moved to the horse's large hindgut for fermentation. The hindgut ferments fibrous feeds such as grasses into usable nutrients. Feral horses generally would not encounter large amounts of feeds high in soluble carbohydrates (found in grains and sugars), which can lead to digestive upset if they reach the hindgut. The horse's digestive tract works strictly in one direction. Horses cannot vomit or belch, so the continuous movement of the horse helps keep food and gases moving through the digestive tract.

Domestic horses kept in a pasture exhibit the same eating habits as feral horses. However, because the pasture is a confined area, domestic horses will have particular areas of the pasture that they overgraze. These areas are called lawns and consist of short grass that is usually of fairly high quality because it grows rapidly. Horses typically defecate in specific areas in the pasture that they usually do not graze (latrine behavior). These areas contain taller, more mature plants and often are referred to as 'roughs.' Normal adult horses will not consume horse feces, but foals do consume fresh feces from mares. This may be a normal way for foals to introduce microbes into the hindgut. Horses also have 'lounging' areas in the pasture that they occupy when they are not eating. Lounging areas are typically near a gate, water trough, or shade and usually contain bare soil with little vegetative cover. The horse's grazing habits can greatly reduce the amount of usable pasture on a farm. Pasture management procedures such as pasture rotation, harrowing, and regular mowing can encourage horses to graze larger areas in the pasture and to waste less grazing space.

Forage

Horses naturally graze, and if your pasture has good-quality grasses such as Kentucky Blue, alfalfa and clover, it will provide a good diet. Althoug you should be aware of high protein overdosing. Hay is a dried combination of many of these grasses. It comes in cubed bales, round bales or pellets. Hay is a good nutrient source. If you store hay, keep it dry and free of mold. Don't confuse hay with straw. Straw is a bedding material that contains no nutritional value.

Potassium Excess

It is easy for grazing horses or horses fed with hay to excess potassium intake. Despite the large excess of intake, this excess appears to be of little concern. The equine kidney is very efficient at removing excess K from the body. When potassium intake is increased, urinary excretion increases, followed by fecal excretion. It has also been found that horses will refuse to eat if given a diet with excess K and deprived of adequate water. This mechanism ensures that toxicity is of very little concern. As long as there is water available to the body, potassium can be excreted through urine...if the horse only takes in K when he has water available, he'll never run into a situation where he has an excess and no ability to excrete it through urine.

The program complements the information provided in the "Nutrient Requirements
of Horses" by performing some of the procedures needed to calculate requirements.
This program is not intended to replace the "Nutrient Requirements of Horses"
book, which contains important information about the many factors that can influence
the derivation and application of nutrient requirements to various situations. Knowledge
of nutrient constraints and limitations of the suggested equations and models is
essential for the proper use of this program in determining the nutrient requirements
of specific horses. Because of the many variables involved and judgments that must
be made in choosing inputs and interpreting outputs, the NRC and HorseMath.com make
no claim for the accuracy of this software in predicting the requirements for individual
horses in specific situations. The user is solely responsible for the risk of use.
Careful review of the information presented in the "Nutrient Requirements of
Horses" will assist users in making appropriate judgments in the use of this
program.